CN101102799B - Method of cardiac imaging with the use of hyperpolarized 13c-pyruvate - Google Patents

Abstract

The invention relates to a method of cardiac imaging using hyperpolarised <13>C-pyruvate as MR imaging agent, which allows determination of the viability of cells in the myocardium.

Description

Use hyperpolarization 13The method of cardiac imaging of C-pyruvate

The present invention relates to a kind of hyperpolarization of using ¹³The C-pyruvate is as the method for cardiac imaging of MR preparation, and this method can be determined the viability of myocardial cell.

Magnetic resonance (MR) imaging (MRI) is a kind of imaging technique, the doctor tends to it especially in the Noninvasive mode, whole or its parts of images of picked-up experimenter health need not as the X-ray experimenter and medical personnel to be exposed in potential harmful lonizing radiation.Because its high-quality image, MRI becomes the imaging technique of rather well received soft tissue and organ such as heart.

Heart and injury that ischemia is relevant and disease are main causes dead in the western countries.Myocardial ischaemia is a kind of serious disease, has only and differentiates fast in early days and the location myocardial ischaemia, can prevent that just the experimenter suffers from the irreversibility cardiac damage.

Heart tissue, the same with other metabolic activity tissue, the ischemia damage appears especially easily.The commitment of acute myocardial infarction is attended by the normal contraction afunction usually, shows by the local motion obstacle.This may be because crown perfusion pressure suddenly reduces, and brings out acute myocardial hibernation state, and normally strides stopping fast of film ion transport.The perfusion again of the ischemia cardiac muscle before irreversible damage begins can be fast or is slowly recovered (myocardial function forfeiture) to normal heart metabolism and function.

Nuclear magnetic resonance has developed into a kind of cardiac imaging technology of practicality.Although the MR technology, can show the anatomical structure of heart with spin-echo-wave imaging, the use of placebo also is that detection myocardial ischaemia and infarction are requisite.One class MR placebo is the paramagnetic placebo, comprising paramagnetic metal ion, for salt form or be complex form with chelating/complexation part complexation.

Paramagnetic placebo GdDTPA (Magnevist ^TM) become myocardial imaging with the main body of clinical trial.Although this metal complex has shown the discriminating of the acute myocardial infarction in the MR image that can improve the animal and human, because it discharges and be distributed in extracellular fluid compartment fast, the clinical practice of its myocardial imaging is restricted.

Mn ²⁺Be applied in the myocardium MR imaging as a kind of paramagnetic metal ion as placebo.It and Ca ²⁺Competition enters cardiac muscle in the contraction by slow calcium channel, produces the relaxation time T1 that significantly shortens and therefore strengthens signal intensity in the normal myocardium tissue.During heart rate and contractility increase, the Mn of per time unit ²⁺Influx improves.But, in the ischemia cardiac muscle, because blood flow reduces, contractility reduces Mn ²⁺Absorption reduce greatly.Therefore, use paramagnetic Mn ²⁺The MR imaging is carried out in agent in contrast, can detect the ischemia cardiac muscle and itself and normal myocardium are organized difference mutually.

But, have some shortcoming with manganese ion.Use manganese salt, have cardiac toxicity as salt such as manganous chloride, thus bring safety issue (see for example Hu et al.Magn.Res.inMedicine 46, (2001), 884-890).Done the toxic action of attempting compensating manganese salt, method is to add calcium salt or give this salt with slow infusion form.Use the shortcoming of calcium to be in the placebo preparation, itself and manganese competition calcium channel enter myocardial cell.This method causes efficient to reduce, and needs the placebo of high dose to compensate this effect subsequently.

WO-A-99/01162 has described a kind of method that detects myocardial ischaemia, uses the manganese complex fast imaging.Imaging process it is said simple and easy to do, finishes in 3-6 hour after injection.As if although this method does not have toxicity problem, obtaining the result from imaging sequence will postpone considerable time, will the long time to giving placebo because begin from imaging sequence.

WO 2004/054623 has described some manganese complex of a kind of usefulness and has differentiated the myocardial ischaemia Method for Area.Physiology and/or pharmacology stress scheme be the parts of this method, because it has increased the contrast difference between normal and local ischemic myocardium, thereby are used low placebo dosage.But this stress scheme increase the weight of experimenter's psychologic stress.

Therefore, need a kind of medicament that in the MR formation method, uses, increase the difference between normal and ischemic tissue, and then estimate the viability of this tissue at cellular level.This medicament also should have safety, does not promptly have toxic and side effects when its clinical dosage.In addition, also need fast and convenient evaluation cardiac muscular tissue, simultaneously not to the experimenter bring additionally stress, do not postpone to treat the MR formation method that detects beginning yet.

WO-A-99/35508 discloses a kind of high T that uses ₁The method of experimenter MR is investigated in agent as the hyperpolarised solution of MR preparation.Term " hyperpolarization " is meant to strengthen and is present in high T ₁NMR active nucleus in the agent (be the nuclear of non-zero nuclear spin, preferred ¹³C-or ¹⁵N-nuclear) nuclear polarization effect.By strengthening the nuclear polarization effect of NMR active nucleus, these nuclears excite and ground state nuclear spin state between overall significant difference enlarge, thereby the MR signal intensity is increased more than 100 times.When using hyperpolarization ¹³C-and/or ¹⁵The high T of N-enrichment ₁During agent, basically not from the interference of background signal, because the natural abundance of C and/or N can ignore, so image contrast is very high.The various possible high T that are suitable for hyperpolarization and are used as the MR preparation are subsequently disclosed ₁Agent, comprising but be not limited to non-endogenous and endogenous compound such as acetate, pyruvate, oxalate or gluconate, sugar is as glucose or fructose, urea, amide, aminoacid such as glutamic acid, glycine, cysteine or aspartic acid, nucleotide, vitamin such as ascorbic acid, penicillin derivant and sulfonamide etc.What further specify is that intermediate in the circulation of homergys such as tricarboxylic acid cycle such as fumaric acid and acetone acid are the preparations that preferably is used for the metabolic activity imaging.

What stress is, the hyperpolarization preparation owing to relaxation and-when giving experimenter's health-dilution decays.Therefore, the T of preparation ₁Value is must be enough in biofluid (for example blood) high, should be enough to make preparation with hyperpolarization distributions highly in the target site of experimenter's health.

We unexpectedly find, hyperpolarization ¹³The C-pyruvate can be used as the preparation of estimating cardiac muscular tissue's viability.The MR signal amplitude that is produced by different pyruvate metabolite changes with the metabolism state of cardiac muscular tissue.Therefore, the graphic finger printing that can be used as heart tissue metabolism state to be detected of metabolic peak of the uniqueness that is formed by these metabolites is to distinguish survival and non-survival myocardium tissue.This just makes hyperpolarization ¹³The C-pyruvate becomes the interior MR preparation of body of splendid evaluation cardiac muscular tissue viability, for example is used to differentiate myocardial ischaemia or heart attack " adventurous tissue " afterwards.This information that exceeds perfusion assessment or the discriminating of dead cardiac muscle tissue begins suitable treatment to the doctor, and further infringement is extremely important to prevent experimenter's cardiac muscle.

Therefore, in first aspect, the invention provides a kind of hyperpolarization of using ¹³The C-pyruvate is estimated the method for cardiac muscular tissue's viability as preparation.

¹³The C-pyruvate is as safe as a house, and as endogenous compound, the human tolerance is good.Use hyperpolarization in the methods of the invention ¹³The C-pyruvate can obtain the result fast, need not delay time between administration and the MR imaging sequence.This just means that the experimenter can receive treatment immediately, thereby improves survival and rehabilitation machines meeting.Not needing in the inventive method stress scheme, thereby more useful to the experimenter.

The NMR activity ¹³The hyperpolarization of C-nuclear can reach (for example, seeing WO-A-99/35508) by the whole bag of tricks, and preferable methods is, parahydrogen method freezing from noble gas polarization transfer, " violence formula ", spin and DNP.For obtaining hyperpolarization ¹³The C-pyruvate preferably directly will ¹³The polarization of C-pyruvate, or will ¹³C-acetone acid polarization and with polar ¹³The C-acetone acid is converted into polar ¹³The C-pyruvate is for example by neutralizing with alkali.

Obtain hyperpolarization ¹³The preferable methods of C-pyruvate is from the hyperpolarized noble gas polarization transfer.Non--zero nuclear spin that noble gas has can for example be used cyclic polarization light by hyperpolarization, can make its polarization level surpass the balance polarization level.Hyperpolarized noble gas, preferred ³He or ¹²⁹Xe or its mist can be used for carrying out ¹³The hyperpolarization of C-nuclear.Hyperpolarization also can obtain by the hyperpolarized noble gas that uses isotope enrichment, and is preferred ³He or ¹²⁹Xe.Hyperpolarized gas can be a gas phase, also can be dissolved in the liquid/solvent, and perhaps hyperpolarized gas itself can be used as solvent.Moreover this gas is condensable to be used in the surface of solids of pre-cooling and with this form, perhaps makes its distillation.Preferably hyperpolarized gas is fully mixed with this chemical compound and polarize.Therefore, if polarization ¹³The C-acetone acid is because it is a liquid in room temperature, so hyperpolarized gas preferably is dissolved in the liquid/solvent or is used as solvent.If polarization ¹³C pyruvate, hyperpolarized gas preferably are dissolved in the liquid/solvent of same dissolving pyruvate.

Obtain hyperpolarization ¹³Another method for optimizing of C-pyruvate is under low-down temperature, in High-Field, to make the polarization of NMR active nucleus with thermodynamic equilibrium.Than the temperature of manipulation fields and NMR spectrum, hyperpolarizing action is finished by using high field and extremely low temperature (violence formula).The used magnetic field intensity height of should trying one's best usually above 1T, preferably is higher than 5T, more preferably is higher than 15T, or more especially preferably is higher than 20T or higher.Temperature should be low as far as possible, as 4.2K or lower, and preferred 1.5K or lower, more preferably 1.0K or lower, especially preferably 100mK or lower.

Obtain hyperpolarization ¹³The other method of C-pyruvate is the spin freezing method.This method contains with the freezing polarization of spin makes solid chemical compound or system's spin polarization.This system is mixed with or evenly is mixed with the suitable paramagnetic material material such as Ni, lanthanum or the actinide ion of crystal form, has three or more axis of symmetry of rule.Instrumentation is simpler than DNP, does not need uniform magnetic field, because need not use the resonant excitation field.By sample is operated around the axle rotation perpendicular to magnetic direction.The precondition of this method is that this paramagnetic meterial has the anisotropy g factor of height.Result as the sample rotation makes electron paramagnetic resonance contact with nuclear spin, causes the decline of nuclear spin temperature.Continue rotary sample, reach new balance until nuclear spin polarization.

In a preferred embodiment, obtain hyperpolarization with DNP (power nuclear polarization) method ¹³The C-pyruvate.Polarization is called paramagnetic agent or DNP agent again and is produced by paramagnetic compound.In the DNP method, energy provides with the microwave irradiation form usually, is used for beginning to excite paramagnetic agent.After decaying to ground state, polarization just is transferred to the NMR active nucleus of sample from the not sharing electron of paramagnetic agent.Usually, in the DNP method, using or highfield and extremely low temperature, for example in liquid helium and about 1T or higher magnetic field, carry out DNP and operate.Perhaps, also can use moderate magnetic field and any temperature that can obtain enough polarization gains.The DNP technology has description in WO-A-98/58272 and WO-A-01/96895, the both incorporates this paper by reference into.For obtaining hyperpolarization by the DNP method ¹³The C-pyruvate can use ¹³The C-pyruvate and/or ¹³The C-acetone acid is as treating polarized compounds.

If use ¹³The C-acetone acid and/or ¹³The C-pyruvate then depends primarily on the used paramagnetic agent in the DNP method.If paramagnetic agent dissolves in ¹³The C-acetone acid then preferably uses ¹³C-acetone acid and liquid mixture, preferably by paramagnetic agent and ¹³The liquid solution that the C-acetone acid forms.If paramagnetic agent is insoluble to ¹³The C-acetone acid, then ¹³The C-pyruvate and/or ¹³C-acetone acid and at least a cosolvent can be used to form liquid mixture, preferred liquid solution.The level that has been found that the success of DNP and polarization depend on treat polar chemical compound with its paramagnetic agent that contacts closely mutually.Therefore, the preferred solubilized paramagnetic agent of cosolvent and ¹³The C-acetone acid and/or ¹³The cosolvent of C-pyruvate or cosolvent mixture.Just ¹³The C-pyruvate, preferred water is as cosolvent.

In addition, also find, form glassy mass when sample mixture in cooling/freezing back but not during crystallized sample, obtained high polarization level by the DNP method.Simultaneously, form hyaline substance make paramagnetic agent with treat that polar mixture contacts more nearly. ¹³The C-acetone acid is that a kind of good hyaline substance forms agent, therefore whenever paramagnetic agent dissolves in ¹³During the C-acetone acid, be preferred in the DNP method. ¹³The C-pyruvate is a kind of salt, and ¹³Can produce crystallized sample after the aqueous solution of C-pyruvate and the liquid mixture of paramagnetic agent are freezing.For avoiding this point, preferably add other good hyaline substance and form agent, as glycerol, propylene glycol or ethylene glycol.

Therefore in one embodiment, ¹³The C-pyruvate aqueous solution that obtains soluble in water adds paramagnetic agent, glycerol and other optional cosolvent and forms liquid mixture.In a preferred embodiment, ¹³C-acetone acid, paramagnetic agent and cosolvent are combined together to form liquid mixture.In a most preferred embodiment ¹³C-acetone acid and paramagnetic agent are combined together to form liquid mixture.The abundant mixing of this chemical compound can reach by several known methods, and for example stirring, whirlpool hang or be ultrasonic.

Before carrying out the DNP method, carry out freezing to liquid compound.The cooling of liquid mixture/freezing can the acquisition by methods known in the art, for example that liquid mixture is freezing in liquid nitrogen, or directly be placed in the polarizer, liquid helium wherein is with freezing this sample.

As mentioned above, power nuclear polarization method (DNP) is a kind ofly will treat polar mixture by the DNP agent, and promptly paramagnetic agent/chemical compound is finished the method for polarization.

Many compound known can be used as the DNP agent, transition metal such as chromium (V) ion for example, organic free radical such as NO free radical (nitroxideradicals), trityl group (tritylradicals) or magnetic-particle.For example, this class DNP agent has narration in WO-A-99/35508, WO-A-88/10419, WO-A-90/00904, WO-A-91/12024, WO-A-93/02711 or WO-A-96/39367.

In a preferred embodiment, the trityl group of formula (I)

Wherein

M represents hydrogen or monovalent cation; And

R1 can be identical or different, the optional hydroxylated C of expression straight or branched ₁-C ₆-alkyl or-(CH ₂) _n-X-R2, wherein n is 1,2 or 3; X is O or S, and R2 is the C of straight or branched ₁-C ₄-alkyl.

As paramagnetic agent, to obtain by the DNP method ¹³The C-pyruvate.

In a preferred embodiment, M represents that hydrogen or monovalence physiology can tolerate cation.Term " physiology can tolerate cation " is meant the cation that people or non-human animal's live body can tolerate.Preferably, M represents hydrogen or base cations, ammonium ion or organic amine ion, for example meglumine ion.Most preferably, M represents hydrogen or sodium.

In another preferred embodiment, R1 can be identical or different, and is preferably identical, and the optional hydroxylated C of expression straight or branched ₁-C ₄-alkyl, most preferable, ethyl, isopropyl, hydroxymethyl or hydroxyethyl.

In another preferred embodiment, R1 can be identical or different, and is preferably identical, and expression-CH ₂-O-(C ₁-C ₃-alkyl) ,-(CH ₂) ₂-O-CH ₃)-(C ₁-C ₃-alkyl)-O-CH ₃,-CH ₂-S-(C ₁-C ₃-alkyl) ,-(CH ₂) ₂-S-CH ₃,-(C ₁-C ₃-alkyl)-S-CH ₃,-CH ₂-O-CH ₃,-CH ₂-O-C ₂H ₅,-CH ₂-O-C ₂H ₄OH ,-CH ₂-CH ₂-O-CH ₃,-CH ₂-S-CH ₃,-CH ₂-S-C ₂H ₅,-CH ₂-S-C ₂H ₄OH or-CH ₂-CH ₂-S-CH ₃, most preferably-CH ₂-CH ₂-O-CH ₃

In a preferred embodiment, M represents hydrogen or sodium, and R1 is identical, and expression-CH ₂-CH ₂-O-CH ₃

The synthetic of the trityl group group of formula (I) can be referring to WO-A-91/12024, WO-A-96/39367, WO 97/09633 and WO-A-98/39277.In brief, can be by with the carboxylic acid derivates reaction of metallized single aryl compound of three molar equivalents with the due care of a molar equivalent, formation trimerization intermediate synthesizes above-mentioned group.This intermediate is metallized, and obtains three carboxyl trityl methanol with reaction such as carbon dioxide subsequently, and in other step, itself and hydroxy acid reaction produce the triaryl methyl cation.This cation is reduced subsequently and forms stable trityl group.

Comprise ¹³The C-pyruvate and/or ¹³The liquid mixture of C-acetone acid and optional solvent preferably contains the trityl group of 5-100mM formula (I), more preferably 10-20mM, preferred especially 12-18mM, most preferably 13-17mM.Have now found that the deadline with the polarization of the group of higher amount in the DNP method is shorter, but its polarization level that reaches is lower.Therefore, these two kinds mutual balances of effect.

This DNP technology has description in WO-A-98/58272 and WO-A-01/96895, the both incorporates this paper by reference into.Generally speaking, in using in the DNP method or highfield and extremely low temperature, for example in liquid helium and carry out DNP in about 1T or the higher magnetic field and operate.Perhaps, can use middle magnetic field and any temperature of the polarization gain that can reach enough.In an embodiment preferred of the inventive method, the DNP method is carried out with about 1T or above magnetic field at liquid helium.Suitable polarization unit description is in WO-A-02/37132.In a preferred embodiment, the polarization unit comprises cryostat and polarization device, and for example microwave office is connected in microwave source in the centre bore by the microwave guider, and around this centre bore round magnetic field generation device such as superconducting magnet.This hole extends to the level in the P district that approaches superconducting magnet at least vertically downward, and the magnetic field intensity at this place is enough high, for example between the 1-25T, is enough to make ¹³C-nuclear polarizes.Sample well is preferably salable, and available low pressure emptying, the pressure of for example about 1mbar or lower magnitude.Sample (promptly contains paramagnetic agent ¹³The C-pyruvate and/or ¹³The mixture of C-acetone acid) gatherer sample transhipment pipe movably for example can be contained in this hole, and the position of microwave office inside in the P district is inserted at the top in this this hole of Guan Kecong downwards.The P district is cooled to enough low temperature with liquid helium, so that produce polarization, the magnitude of preferred temperature is 0.1-100K, more preferably 0.5-10K, most preferably 1-5K.The upper end of preferred sample gatherer is salable, can adopt any suitable sealing means to reach the partial vacuum in the hole.The sample preserving container keeps cup as sample, can move freely the inside with accommodate sample gatherer lower end.Preferably by the light material of low specific heat capacity and good cryogenic properties, for example KeIF (polychlorotrifluoroethylene) or PEEK (polyether-ether-ketone) make the sample preserving container.Shuttle can hold one or more and treat polar sample.

Sample is inserted in the sample preserving container, be immersed in the liquid helium and also use microwave irradiation, preferably under 200mW, frequency is about 94GHz.Polarization level can be absorbed the solid of sample during microwave irradiation ¹³Therefore the C-NMR signal is monitored, and uses the device that contains the unit that polarize to come obtaining step b) in solid-state C-NMR spectrum for preferably.Usually, use ¹³The C-MR signal was mapped to the time, obtained saturation curve.Therefore, might determine when the polarization level that reaches optimization.

If a kind of polarization method for example DNP method needs solid-state sample, then solid sample must change into liquid, to use in the methods of the invention.The mixture that perhaps solid polarized dissolving is as described in WO-A-02/37132, perhaps with its fusion, as described in WO-A-02/36005.Preferably, more preferably be dissolved in the buffer, in the preferred physiological tolerance buffer, to obtain fluid composition with solid hyperpolarization sample dissolution.Term among the application " buffer " is meant one or more buffer, promptly is also referred to as buffer solution mixture.

Preferred buffer is the physiological tolerance buffer, more preferably from about the buffer of pH 7-8, for example phosphate buffer (KH ₂PO ₄/ Na ₂HPO ₄), ACES, PIPES, imidazoles/HCl, BES, MOPS, HEPES, TES, TRIS, HEPPS or TRICIN.Preferred buffer is phosphate buffer and TRIS, most preferably is TRIS.In another embodiment, use more than one above-mentioned preferred buffer, i.e. buffer solution mixtures.

When ¹³The C-acetone acid when treating polar chemical compound, dissolving also comprise with ¹³The C-acetone acid is converted into ¹³The C-pyruvate.For reaching this purpose, will ¹³C-acetone acid and alkali reaction.In one embodiment, ¹³C-acetone acid and alkali reaction are converted into ¹³The C-pyruvate also adds buffer subsequently.In another embodiment, buffer and alkali mix in same solution, and this solution is joined ¹³In the C-acetone acid, simultaneously with its dissolving and change into ¹³The C-pyruvate.In a preferred embodiment, alkali is NaOH, Na ₂CO ₃Or NaHCO ₃Aqueous solution, most preferred alkali is NaOH.In an especially preferred embodiment, dissolve with the TRIS buffer that contains NaOH ¹³The C-acetone acid also is translated into ¹³The C-Sodium Pyruvate.

In another preferred embodiment, buffer or combination buffer/aqueous slkali (if use) also comprise one or more and can combine with free paramagnetic ion or the chemical compound of complexation, for example chelating agen such as DTPA or EDTA.Have now found that free paramagnetic ion can shorten the T of hyperpolarised compound ₁, this point will preferably be avoided.

Preferably dissolve with disclosed method among the WO-A-02/37132 and/or device.If carry out hyperpolarization with the DNP method, then LU can separate physically with polarizer, perhaps can be the part of the device that contains polarizer and LU.In a preferred embodiment, be dissolved in the highfield and carry out, to increase relaxation and to keep maximum hyperpolarization.Should avoid joint (node), low simultaneously field can cause relaxation to strengthen and no matter above-mentioned measured value how.

If carry out hyperpolarization by the DNP method, paramagnetic agent and/or its product are preferably from containing ¹³Remove in the solution of C-pyruvate.Paramagnetic agent and/or product can removal partly, substantially or fully, preferably removals fully.Product can be ester suc as formula the trityl group of (I), and this ester can form by acetone acid and the reaction of formula (I) hydroxyl group.The method that is used to remove paramagnetic agent and/or its product is known in the art.Generally speaking, the method for Shi Yonging depends on the character of paramagnetic agent and/or its product.When polarizing back dissolved solid sample, this group can precipitate, and is easy to separate from fluid composition by filtering.If magnetic-particle is as paramagnetic agent, these granules are easy to equally by removing by filter.If precipitation does not take place, can remove paramagnetic agent by chromatographic separation technology, this technology has liquid chromatograph such as reverse or ion exchange chromatography, perhaps removes by extracting.

Because the trityl group of formula (I) has ultraviolet-visible absorption spectroscopy, might use the UV, visible light absorption process to detect the amount that is present in after it is removed in the fluid composition.In order to obtain quantitative result, the concentration of this group that exists in the promptly dissolved hyperpolarization sample, can be with the spectrophotometric meter calibrating so that the absorbtivity of specific wavelength accurately corresponding to the concentration of corresponding group in the sample.

Use in the inventive method ¹³C-pyruvate and/or be preferred for obtaining hyperpolarization by the DNP method ¹³The C-pyruvate ¹³C-acetone acid, its isotope enrichment preferably at least 75%, more preferably at least 80%, especially preferably at least 90%, it is most preferred that isotope enrichment surpasses 90%.Optimal enrichment is 100%. ¹³The C-acetone acid and/or ¹³The isotope of C-pyruvate can be enriched in the C1-position, and (following table is shown ¹³C ₁-acetone acid and ¹³C ₁-pyruvate), (following table is shown in the C2-position ¹³C ₂-acetone acid and ¹³C ₂-pyruvate), (following table is shown in the C3-position ¹³C ₃-acetone acid and ¹³C ₃-pyruvate), (following table is shown C1-and C2-position ¹³C _1,2-acetone acid and ¹³C _1,2-pyruvate), (following table is shown C1-and C3-position ¹³C _1,3-acetone acid and ¹³C _1,3-pyruvate), (following table is shown C2-and C3-position ¹³C _2,3-acetone acid and ¹³C _2,3-pyruvate) or (following table is shown C1-, C2-and C3-position ¹³C _1,2,3-acetone acid and ¹³The C-pyruvate); The C1-position is preferred.

¹³The C-acetone acid and ¹³C ₁Several synthetic methods of-pyruvate are known in the art.In brief, Seebach et al., Journal of Organic Chemistry 40 (2), 1975; 231-237 has described its route of synthesis, and this approach depends on protection and activates raw material such as the S that contains carbonyl, S-acetal; as 1,3-dithiane or 2-methyl isophthalic acid, 3-dithiane.Described dithiane is metallized, and with contain methyl compound and/or ¹³CO ₂Reaction.By using suitable isotope enrichment that this paper lists ¹³The C-chemical compound might obtain ¹³C ₁-pyruvate, ¹³C ₂-pyruvate or ¹³C _1,2-pyruvate.The carbonyl function is subsequently by using the conventional method of describing in the document to recover.Begin that from acetic acid different route of synthesis is arranged, at first be converted into acetyl bromide, then with Cu ¹³The CN reaction.The nitrile of gained is converted into acetone acid (seeing for example S.H.Anker et al., J.Biol.Chem.176 (1948), 1333 or J.E.Thirkettle, Chem Commun. (1997), 1025) through amide.In addition, ¹³The C-acetone acid can be used United States Patent (USP) 6,232, and the method described in 497 is with commercially available ¹³The C-pyruvate is protonated to be obtained.

In order to use hyperpolarization in the methods of the invention ¹³The C-pyruvate provides as the form of the compositions that is suitable for giving live body people or non-human animal's body.Said composition preferably comprises the mixture of above-mentioned buffer or buffer.Said composition also comprises conventional pharmaceutical can accept carrier, excipient and formulation auxiliary agents.

Therefore, described compositions can for example comprise stabilizing agent, Osmolyte regulator, solubilizing agent etc.

Pyruvate is an endogenous compound, and the human tolerance is good, even also is like this during high concentration.As the precursor in the tricarboxylic acid cycle, pyruvate has been brought into play important metabolism in human body.Pyruvate is converted into different chemical compounds: its transamination produces alanine, and through the effect of oxidative deamination base, pyruvate is converted into acetyl-CoA and bicarbonate, and its reduction produces lactate, and its carboxylation produces oxaloacetate.

Have now found that hyperpolarization ¹³The C-pyruvate is converted into hyperpolarization ¹³C-lactate, hyperpolarization ¹³The C-bicarbonate (only exists ¹³C ₁-pyruvate, ¹³C _1,2-pyruvate or ¹³C _1,2,3Under the situation of-pyruvate) and hyperpolarization ¹³The conversion process of C-alanine is used in the MR imaging in vivo distinguishing vigor and non-vigor cardiac muscular tissue is arranged.This point is beat all, because people generally believe the T of hyperpolarised compound ₁Owing to relaxation and dilution decay.In 37 ℃ of whole bloods of people, ¹³The T of C-pyruvate ₁Relaxation time is about 42s, but finds hyperpolarization ¹³The C-pyruvate is converted into hyperpolarization ¹³C-lactate, hyperpolarization ¹³C-bicarbonate and hyperpolarization ¹³The speed of the conversion process of C-alanine near be enough to make from ¹³The signal of C-pyruvate parent compound and metabolite thereof is detected.Alanine, bicarbonate and Lactated amount depend on the metabolism state of waiting to investigate cardiac muscular tissue.Hyperpolarization ¹³C-lactate, hyperpolarization ¹³C-bicarbonate and hyperpolarization ¹³The MR signal intensity of C-alanine and the amount of these chemical compounds and when detecting remaining degree of polarization relevant, therefore by the monitoring hyperpolarization ¹³The C-pyruvate is converted into hyperpolarization ¹³C-lactate, hyperpolarization ¹³C-bicarbonate and hyperpolarization ¹³The conversion process of C-alanine might be with the internal metabolism engineering of Noninvasive MR imaging research people or non-human animal's heart tissue.

Hereinafter, term " hyperpolarization ¹³The C-pyruvate ", " ¹³The C-pyruvate " and " pyruvate " is used interchangeably.Same term " the hyperpolarization in addition that is suitable for ¹³The C-lactate ", " ¹³The C-lactate " and " lactate "; " hyperpolarization ¹³The C-alanine ", " ¹³The C-alanine " and " alanine "; " hyperpolarization ¹³The C-bicarbonate ", " ¹³The C-bicarbonate " and " bicarbonate " and " hyperpolarization ¹³The C-metabolite ", " ¹³The C-metabolite " and " metabolite ".

Have now found that the metabolism state of cardiac muscular tissue is depended in the variation of the MR signal amplitude that different pyruvate metabolite produces.Therefore, the graphic finger printing that can be used as cardiac muscular tissue to be detected metabolism state of unique metabolic peak of alanine, lactate, bicarbonate and pyruvate has vigor, non-vigor and adventurous cardiac muscular tissue thereby distinguish.Determining the viability of cardiac muscular tissue, is very important after myocardial ischaemia or heart attack, and also very important for the experimenter who suffers from diabetes and metabolism syndrome, these diseases all can produce myocardial tissue damage.

Because coronary heart disease (CAD) has various clinical symptoms, to sudden death, therefore can report that the diagnostic method of cell survival state can bring direct benefit from stable type angor.Between the situation of normal stabilized cell and dead cell these two kinds " extremely ", in ischemia cardiac muscular tissue, also there are the different situations of many cellular levels, these situations cause various clinical symptoms again.It is important, differentiate the different situations in these ischemia cardiac muscular tissues, be called " adventurous cardiac muscular tissue " again, promptly do not treat ischemia and can increase the weight of to cause downright bad tissue, thereby to provide suitable treatment to prevent downright bad generation to the experimenter.

Two kinds of differences of ischemia heart but very serious state are myocardial hibernation and myocardial function forfeiture.Myocardial hibernation is a kind of chronic ischemia state, and wherein myocardial blood flow reduces, the corresponding reduction of cardiac function.Oxidable most fatty acids under the myocardial cell normal condition.In the myocardial hibernation cell, the picked-up of glucose increases (learning) from FDG-PET research, and the prompting pyruvate will be the preferred substrates of these cells.Myocardial function forfeiture is another kind of acute ischemic (a for example main coronary occlusion), and the normal but function of its blood flow reduces.Because low relatively metabolic activity, this will cause low lactate.Have now found that, because it has low ¹³C-bicarbonate and/or height ¹³Therefore C-lactate signal can differentiate adventurous cardiac muscular tissue with the inventive method.

Ischemia can produce myocardial dysfunction in various degree, and if serious and drag for a long time excessively, can cause necrocytosis.Under the latter event, cell death and metabolism does not take place for example gives hyperpolarization ¹³During the C-pyruvate, ¹³Can only obtain this signal in C-spectrum and/or the image and do not exist may metabolite signal.

Generally speaking, experimenter to be detected, for example experimenter or animal are placed in the MR magnet.Use special use ¹³C-MR RF-coil is around zone to be detected.

Comprise ¹³The image forming medium of C-pyruvate and one or more conventional pharmaceutical carriers, excipient and/or additive gives through parenteral, and preferred intravenous or intra-arterial give.It also is possible directly giving heart, for example image forming medium is injected through placing conduit coronarius.The dosage of image forming medium and concentration depend on multiple factor, for example toxicity and route of administration.Usually, the administration concentration of image forming medium is up to 1mmol pyruvate/kg body weight, preferred 0.01-0.5mmol/kg, more preferably 0.1-0.3mmol/kg.Medicine-feeding rate preferably is lower than 10ml/s, more preferably less than 6ml/min, and 5ml/s-0.1ml/s most preferably.After the administration in the 400s, in the preferred 120s, more preferably in the 60s, preferred especially 20-50s, most preferably 30-40s uses the MR imaging sequence (sequence) with frequency and spatial selectivity mode assembly coding volume to be detected.This will produce ¹³The C-lactate, ¹³The C-alanine and ¹³The metabolic images of C-pyruvate, more preferably ¹³The C-lactate, ¹³The C-alanine, ¹³The metabolic images of C-bicarbonate and C-pyruvate.

Can use to be called the spectroscope imaging sequence, and the coding that obtains volume to be detected as mentioned below (T.R.Brown et al., Proc.Natl.Acad.Sci.USA 79,3523-3526 (1982); A.A.Maudsley, et al., J.Magn.Res 51,147-152 (1983)).The spectroscope imaging data contains the element of mentioning of some, and wherein each element contains full C-MR spectrum.The C-pyruvate and ¹³The C-metabolite exists ¹³All have its unique position in the C-MR spectrum, and their resonant frequency can be used to differentiate them.The integration at the peak of its resonant frequency respectively with ¹³The C-pyruvate and ¹³The amount of C-metabolite is directly related.When with time domain match approach, as L.Vanhamme et al., J Magn Reson 129, the described assessment of 35-43 (1997) ¹³C-pyruvate and each ¹³During the amount of C-metabolite, can produce ¹³C-pyruvate and each ¹³The image of C-metabolite, the decoding of wherein coloured decoding or Lycoperdon polymorphum Vitt have been represented and have been detected ¹³C-pyruvate and each ¹³The amount of C-metabolite.

Though the spectroscope formation method is for example being examined with various MR ¹H, ³¹P, ²³Na produces and embodies its value in the metabolic images, but the required amount of repetition of the spectroscope image of encoding fully makes this method be unsuitable for hyperpolarization ¹³C.In the process of the overall MR data of picked-up, must careful operation to guarantee hyperpolarization ¹³The C-signal is effective.To reduce signal with respect to noise is cost, obtains this point by reducing the RF-pulse angle of using in each phase coding step.High substrate size needs more heterogeneous coding step and longer sweep time.

Based on P.C.Lauterbur (Nature, 242,190-191, (1973) and P.Mansfield (J.Phys.C.6, the formation method of initiative work L422-L426 (1973)), mean in data acquisition to use and read gradient, make it possible to obtain the signal that improves with respect to noise figure picture or its equivalent, the spatial discrimination image of raising.But the primitive form of these formation methods can not draw independently ¹³C-pyruvate and its ¹³C-metabolite image can only draw and contain ¹³C-pyruvate and all ¹³The image of C-metabolite signal, i.e. the discriminating of specific metabolite is impossible.

In a preferred embodiment, used imaging sequence, this sequence is used many echoes frequency information of encoding.This sequence can produce independently water and fat ¹The H-image, for example at G.Glover, J Magn Reson Imaging 1991; 1:521-530and S.B.Reeder et al., MRM 5135-45 has narration in (2004).Since metabolite to be detected with and the MR frequency be known, the method for discussing in this list of references can be used to obtain ¹³The C-pyruvate, ¹³The C-alanine and ¹³The C-lactate, preferred ¹³The C-pyruvate, ¹³The C-alanine, ¹³The C-lactate and ¹³The through image of C-bicarbonate.This process is more effectively utilized hyperpolarization ¹³The C-MR signal, than the spectroscope imaging, it provides better signal quality, higher spatial resolution and absorbing the time faster.

As previously mentioned, great-hearted heart tissue is characterised in that the hypermetabolism activity.During ischemia, when promptly blood flow reduces in the tissue, cell oxygen supply deficiency, the metabolism of cellular level reduces.Unexpectedly, this visible metabolic variation in short MR imaging time window might be used hyperpolarization ¹³The C-pyruvate is used.Significant especially in the cardiac muscular tissue ¹³The C-lactate and ¹³C-bicarbonate signal changes the metabolism state that depends on individual cells, can estimate the viability of myocardial cell.

Therefore, in a preferred embodiment, method of the present invention comprises:

(a) will contain hyperpolarization ¹³The compositions of C-pyruvate gives the experimenter in advance, obtains from the experimenter ¹³C-pyruvate and containing ¹³The metabolite alanine of C, lactate and optional bicarbonate directly ¹³The C-MR image,

(b) optional with a kind of metabolite ¹³C signal and detected other metabolite ¹³C signal correction connection is with according to two, preferred three, most preferably four ¹³Signal strength differences between the C metabolite obtains contrast.

Therefore, in another preferred embodiment, method of the present invention comprises:

(a) will contain hyperpolarization ¹³The compositions of C-pyruvate gives the experimenter in advance, obtains from the experimenter ¹³C-pyruvate and containing ¹³The metabolite alanine of C, lactate and optional bicarbonate directly ¹³The C-MR image,

(b) optional with a kind of metabolite ¹³C signal and detected any other metabolite ¹³C signal correction connection is with according to two, preferred three, most preferably four ¹³Signal strength differences between the C metabolite obtains contrast.

(c) minimum by differentiating ¹³C-bicarbonate signal and/or the highest ¹³C-lactate signal, thus in described image, identify risky cardiac muscular tissue.

For carrying out the correction of pyruvate signal aspect, be maximum in each individual images with metabolite (lactate, alanine and bicarbonate) and pyruvate image standardization (normalized).The second, normalized lactate image be multiply by (multiplied) pyruvate inverted image (inverted pyruvate image), for example maximum pyruvate signal deducts pyruvate level (level) in each pixel in the image.At last, the intermediate object program that obtains in the aforesaid operations multiply by initial lactate image.

Illustrate, for carrying out the correction of bicarbonate signal aspect, lactate and bicarbonate image standard are turned to maximum in each image.Normalized lactate image be multiply by the pyruvate inverted image, and for example maximum pyruvate signal deducts pyruvate level in each pixel in the image.At last, the intermediate object program that obtains in the aforesaid operations multiply by initial lactate image.In a comparable manner, the alanine signal can be included in the analysis, find that low carbon acid hydrogen salt signal and constant alanine signal also can be used as the adventurous indication of cardiac muscular tissue.

For highlighting the district that metabolism changes, in the similar operations that the metabolite signal combination of the metabolite signal that improves and reduction can be applied to describe in the above paragraph together, and then obtain the metabolite image of weighting.Beat all is to the evaluation of cardiac muscular tissue's viability, promptly to vigor being arranged, the differentiation between damage and debility cardiac muscular tissue being arranged, to improve equally by proofreading and correct.

Anatomy and/or perfusion information can be included in cardiac muscular tissue's viability evaluation according to the inventive method.Anatomic information can by with or need not suitable placebo absorb proton or ¹³The C-MR image obtains.Relative perfusion in the cardiac muscle can be by using for example Omniscan of MR placebo ^TMDetermine.Equally, to measure the MR imaging technique be known in the art in the perfusion that need not to give placebo.In a preferred embodiment, non-metabolic hyperpolarization ¹³The C-placebo is used for determining quantitative perfusion.Suitable technique and placebo are described in WO-A-02/23209.In a preferred embodiment, hyperpolarization ¹³The C-pyruvate is used for determining quantitative perfusion.

In another preferred embodiment, comprise hyperpolarization ¹³The image forming medium of C-pyruvate is repeated to give.This is the advantage that has of the inventive method, and other MR formation method uses the medicine based on manganese, and this medicine shows the cardiac toxicity effect when high dose.Because the toxicity of pyruvate is low and safe, the experimenter can tolerate repeat administration well.

The result who obtains in the inventive method can make the doctor pass through suitable treatment is selected in experimenter's inspection.In another preferred embodiment, the inventive method is used for determining whether treatment is successful.

Report that also pyruvate can influence contractility.Therefore, this chemical compound can be simultaneously as diagnosis and therapeutic agent under the situation of the myocardial function forfeiture that oxygen-derived free radicals may be played a role.

On the other hand, the invention provides hyperpolarization ¹³The purposes of C-pyruvate is used for preparing at the MR formation method and uses to estimate the image forming medium of cell viability.

Contain hyperpolarization ¹³C is specified in the 11-14 page or leaf as the image forming medium of preparation.

On the other hand, the invention provides ¹³The C-acetone acid or ¹³The purposes of C-pyruvate, be used for preparing the MR formation method as preparation use with estimate cell viability hyperpolarization ¹³The C-pyruvate.

From ¹³The C-acetone acid or ¹³The C-pyruvate prepares hyperpolarization ¹³The preparation and the embodiment preferred of C-pyruvate are specified in the 5-11 page or leaf.

In a preferred embodiment, the invention provides hyperpolarization ¹³The purposes of C-pyruvate is used for preparing at the MR formation method and uses to estimate the image forming medium of cell viability, and described method comprises:

(a) will contain hyperpolarization ¹³The compositions of C-pyruvate gives the experimenter in advance, obtains from the experimenter ¹³C-pyruvate and containing ¹³The metabolite alanine of C, lactate and optional bicarbonate directly ¹³The C-MR image,

(b) optional with a kind of metabolite ¹³C signal and detected any other metabolite ¹³C signal correction connection is with according to two, preferred three, most preferably four ¹³Signal strength differences between the C metabolite obtains contrast.

In a further preferred embodiment, the invention provides ¹³The C-acetone acid or ¹³The purposes of C-pyruvate is used for preparing at the MR formation method and uses to estimate the hyperpolarization of cell viability as preparation ¹³The C-pyruvate, described method comprises:

(a) will contain hyperpolarization ¹³The compositions of C-pyruvate gives the experimenter in advance, obtains from the experimenter ¹³C-pyruvate and containing ¹³The metabolite alanine of C, lactate and optional bicarbonate directly ¹³The C-MR image,

(b) optional with a kind of metabolite ¹³C signal and detected other metabolite ¹³C signal correction connection is with according to two, preferred three, most preferably four ¹³Signal strength differences between the C metabolite obtains contrast.

The embodiment preferred of said method and this method is described in detail in the 17-20 page or leaf.

Embodiment

Embodiment 1: synthetic three (8-carboxyl-2,2,6,6-(four (methoxy ethyl) benzo-[and 1,2-4,5 '] two-(1,3) dithia cyclopentenes-4-yl) the methyl sodium salt

With 10g according to synthetic (70mmol) three of the method for the embodiment 7 of WO-A1-98/39277 (8-carboxyl-2,2,6,6-(four (hydroxyethyl) benzo-[and 1,2-4,5 ']-two-(1,3)-dithia cyclopentenes-4-yl) the methyl sodium salt, at the argon low suspension in the 280ml dimethyl acetylamide.Add sodium hydride (2.75g), add methyl iodide (5.2ml) then, the reaction of slight exotherm was carried out 1 hour, in 34 ℃ of water-baths 60 minutes.Every kind of sodium hydride and methyl iodide are added twice again with identical amount, behind last the interpolation,, pour into then in the 500ml water mixture stirring at room 68 hours.PH is transferred to pH＞13 with 1M NaOH (aq), with mixture stirring at room 15 hours, the methyl ester that hydrolysis forms.Then mixture is acidified to pH with 50ml 2M HCl (aq) and is about 2, with 3 (500ml and 2 * 200ml) of ethyl acetate extraction.The organic facies Na that merges ₂SO ₄Drying is evaporated to dried then.Crude product (24g) uses acetonitrile/water as the eluant purification by preparation HPLC.The flow point that evaporation is collected is removed acetonitrile.Remaining water ethyl acetate extraction, the organic facies dried over sodium sulfate is evaporated to dried then.Add entry (200ml) in the residue, with 0.1M NaOH (aq) pH carefully is adjusted to 7, residue slowly dissolves in this process.After the neutralization, with the aqueous solution lyophilizing.

Embodiment 2: use by the DNP method ¹³The trityl group preparation of C-acetone acid and embodiment 1 contains hyperpolarization ¹³The compositions of C-pyruvate

The group of 5.0mg embodiment 1 is dissolved in ¹³C ₁The solution of preparation 20mM in the-acetone acid (164 μ l).With the sample mixing, the aliquot of solution (41mg) is put into specimen cup and inserted the DNP polarizer.

Sample is under the DNP condition, in 1.2K, in 3.35T magnetic field, with microwave irradiation (93.950GHz).Stop polarization after 2 hours, sample is dissolved in the aqueous solution of sodium hydroxide and three (hydroxymethyl)-aminomethane (TRIS) according to WO-A-02/37132 with dissolver, obtain hyperpolarization ¹³C ₁The neutral solution of-Sodium Pyruvate.Dissolved sample is used ¹³The C-NMR rapid analysis estimates polarization effect, obtains 19.0% ¹³The C polarizability.

Embodiment 3: use by the DNP method ¹³The trityl group of C-acetone acid and embodiment 1 produces and contains hyperpolarization ¹³The compositions of C-pyruvate

The group (209.1mg) of embodiment 1 is dissolved in ¹³C ₁The solution of preparation 15mM in the mixture of-acetone acid (553mg) and unlabelled acetone acid (10.505g).With the sample mixing, the aliquot of solution (2.015g) is put into specimen cup and inserted the DNP polarizer.

Sample is under the DNP condition, in 1.2K, in 3.35T magnetic field, with microwave irradiation (93.950GHz).Stop polarization after 4 hours, sample is dissolved in the aqueous solution of sodium hydroxide and three (hydroxymethyl)-aminomethane (TRIS) according to WO-A-02/37132 with dissolver, obtain hyperpolarization ¹³C ₁The neutral solution of-Sodium Pyruvate, the total concentration of the pyruvate in 100mM TRIS buffer is 0.5M.Dissolver and chromatographic column are in series.Chromatographic column is for containing hydrophobic packing material (Bondesil-C18,40UM Part #:12213012) post (D=38mm (Varian); H=10mm).The sample of solution absorbs the chromatographic column of this group by selectivity.Filtering solution is used ¹³Polarization effect is estimated in the C-NMR rapid analysis, obtains 16.5% ¹³The C polarizability.Residual radical concentration is analyzed at 469nm with the UV spectrophotometer subsequently, determines that it is lower than the detectability of 0.1 μ M.

Embodiment 4: use by the DNP method ¹³C-acetone acid and three (8-carboxyl-2,2,6,6-four (hydroxyl-ethyoxyl) methyl-benzo [1,2-d:4,5-d '] two (1,3) dithia cyclopentenes-4-yl) methyl sodium salt produces hyperpolarization ¹³The C-pyruvate

Three (8-carboxyl-2,2,6,6-four (hydroxyl-oxethyl) methyl-benzo [1,2-d:4,5-d ']-two-(1,3)-dithia cyclopentenes-4-yl) methyl sodium salt synthetic as described in the embodiment 29 of WO-A-97/09633.

Three (8-carboxyl-2,2,6,6-four (hydroxyl-oxethyl) methyl-benzo [1,2-d:4,5-d ']-two-(1,3)-dithia cyclopentenes-4-yl) methyl sodium salt is dissolved in ¹³C ₁The solution of preparation 20mM in the-acetone acid (83.1mg).With the sample mixing, put into specimen cup and insert the DNP polarizer.Sample is under the DNP condition, in 1.2K, in 3.35T magnetic field, with microwave irradiation (93.950GHz).Obtain sample with Varian Inova-200 NMR spectrogrph ¹³The C-NMR signal.With ¹³The thermal balance measured value of C-NMR signal and enhanced NMR signal is calculated DNP gain (enhancement).Obtain 16% ¹³The C polarizability.

Embodiment 5: cardiac imaging sequence of the present invention

5.1 pig preparation

With infusion pump with the speed of 0.6ml/min with contain isoosmotic NaCl (26vol%), Ketalar (50mg/ml) (Pfizer AB) (42vol%), Norcuron (10mg+5ml sterilized water) (Organon) anaesthetize pig (25kg) by (21vol%) and midazolam (5mg/ml) (Pharma Hameln) cocktail agent (11%vol).

Injection first ¹³C ₁Behind-the pyruvate, pig is taken off from the MR scanner.Under the X ray guiding, ballon catheter is inserted left coronary artery, circumflex artery (circumflexa) was stopped up 15 minutes.In the whole operation process, measure ECG and blood pressure.The ischemia stage finishes back 90 minutes, once more to the pig imaging, obtains and contrast (roughly) same position ¹³The C-image.

5.2 proton MR imaging

Pig is placed pig MR coil (Rapid Biomedical, Germany) also with the library imaging of standard clinical heart proton MR imaging sequence, obtain anatomic information, and obtain the view (, can see the example of short axis view) of the short-axis direction of cardiac muscle referring to the proton reference image among the figure.

5.3 ¹³The C-MR imaging

Proton frequency based on the MR system records calculates according to following equation ¹³C ₁The MR frequency of-alanine:

¹³C ₁The frequency of-alanine=0.25144 * [(system's proton frequency * 1.00021)-0.000397708]

Calculate the frequency of gained, determined ¹³C ₁-alanine produces the position of MR signal in resonance, ¹³C ₁-lactate is positioned at ¹³C ₁The left side of-alanine, ¹³C ₁-pyruvate with ¹³C ₁The resonance of-bicarbonate is positioned at ¹³C ₁The right of-alanine.The MR spectral sequence of operation no-fix is to guarantee ¹³C-MR coil and system's MR frequency are set correctly. ¹³The C-picture position is covered in cardiac muscle and goes up (short axis view) (slice thickness 20mm, planar pixel size 7.5 * 7.5mm ²).Rebuilding the stage, view data is being carried out filling at zero point (zero-filled), to produce 3.75 * 3.75 * 20mm ³Resolution.At 12s (1.3ml/s) in the time, with 16ml's ¹³C ₁-pyruvate (327mM) intravenous injection (0.22mmol/kg) is gone in the foreleg, behind the injection beginning 30s (i.e. injection finishes back 18s), and the beginning chemical shift ¹³The C-MR sequence.

5.4MR the analysis of imaging data

The MR imaging produces the matrix that contains 16 * 16 elements, and wherein each element or voxel/pixel comprise ¹³C-MR spectrum.Rebuilding the stage, matrix is fills up to 32 * 32 zero point, a kind of mathematical operations that helps improve spatial resolution.The software analysis data set that on the MRI scanner, provides with the manufacturer.Produce ¹³The C-pyruvate, ¹³The C-alanine, ¹³The C-lactate and ¹³The metabolic images of C-bicarbonate.

5.5 result

Before stopping up circumflex artery and afterwards the result of the test of gained shows and is summarized in the accompanying drawing.

Fig. 1 had shown ischemia before the stage, image of pig and spectrogram, wherein

Fig. 1 a shows ¹³C-pyruvate image

Fig. 1 b shows ¹³C-lactate image

Fig. 1 c shows ¹³C-alanine image

Fig. 1 d shows proton reference anatomical images

Fig. 1 e shows ¹³C-bicarbonate image, and

Fig. 1 f shows the pixel be selected from image shown in Fig. 1 e ¹³The C-NMR spectrogram

Fig. 2 has shown ischemia after the stage, image of pig and spectrogram, wherein

Fig. 2 a shows ¹³C-pyruvate image

Fig. 2 b shows ¹³C-lactate image

Fig. 2 c shows ¹³C-alanine image

Fig. 2 d shows proton reference anatomical images

Fig. 2 e shows ¹³C-bicarbonate image, and

Fig. 2 f shows the pixel be selected from image shown in Fig. 2 e ¹³The C-NMR spectrogram.

Accompanying drawing demonstrates, before the ischaemic stage and proton reference image afterwards do not have difference. In addition, bicarbonate signal (than contrast) significantly reduces, and the contrast of the positive of lactate signal shows that cardiac muscular tissue is dangerous. Before the ischaemic stage and afterwards alanine and acetonate image do not have difference.

5.6 conclusion

By using hyperpolarization¹³The C-acetonate can be differentiated adventurous cardiac muscular tissue as the preparation in the MR imaging check.

Claims (17)

1. hyperpolarization ¹³The C-pyruvate is used for preparing the purposes in the image forming medium that the MR formation method of estimating cardiac muscular tissue's viability uses.

2. the purposes of claim 1, described hyperpolarization ¹³The C-pyruvate is as the MR image forming medium, to estimate cardiac muscular tissue's viability by following steps

(a) will contain hyperpolarization ¹³The compositions of C-pyruvate gives the experimenter in advance, obtains from the experimenter ¹³C-pyruvate and containing ¹³The metabolite alanine of C, lactate and optional bicarbonate directly ¹³The C-MR image,

(b) optional with a kind of metabolite ¹³C signal and detected any other metabolite ¹³C signal correction connection is with according to two ¹³Signal strength differences between the C metabolite obtains contrast.

3. the purposes of claim 2, wherein step (b) by optional with a kind of metabolite ¹³C signal and detected any other metabolite ¹³C signal correction connection is with according to three ¹³Signal strength differences between the C metabolite obtains recently carrying out.

4. the purposes of claim 2, wherein step (b) by optional with a kind of metabolite ¹³C signal and detected any other metabolite ¹³C signal correction connection is with according to four ¹³Signal strength differences between the C metabolite obtains recently carrying out.

5. each purposes among the claim 1-4, described hyperpolarization ¹³The C-pyruvate is as image forming medium, further to estimate cardiac muscular tissue's viability by following steps

(c) minimum by differentiating ¹³C-bicarbonate signal and/or the highest ¹³C-lactate signal, thus in described image, identify risky cardiac muscular tissue.

6. each purposes, wherein hyperpolarization among the claim 1-4 ¹³The C-pyruvate passes through will with the DNP method ¹³The C-acetone acid and/or ¹³C-pyruvate hyperpolarization obtains.

7. each purposes among the claim 1-4 wherein contains ¹³The image forming medium of C-pyruvate also contains one or more and is selected from following buffer agent: KH ₂PO ₄/ Na ₂HPO ₄, ACES, PIPES, imidazoles/HCl, BES, MOPS, HEPES, TES, TRIS, HEPPS and TRICIN.

8. each purposes among the claim 2-4, wherein with the imaging sequence of many echoes coding frequency informations be used to absorb in the step a) directly ¹³The C-image.

9. each purposes among the claim 2-4, wherein in the step a) directly ¹³The C-image is containing ¹³Picked-up in the 400s after the compositions of C-pyruvate.

10. each purposes among the claim 2-4, wherein absorb other one or more with or without the proton images of proton MRI placebo, or absorb other one or more and use hyperpolarization ¹³The C-MR placebo ¹³The C image is to obtain anatomy and/or perfusion information.

11. the purposes of claim 10, wherein other proton images are used or are absorbed without proton MRI placebo, to determine the relative perfusion in the cardiac muscle.

12. the purposes of claim 10 is wherein other ¹³The C-image is with non-metabolic hyperpolarization ¹³The picked-up of C-MR placebo is to determine the quantitative perfusion in the cardiac muscle.

13. the purposes of claim 10 is wherein other ¹³C-image hyperpolarization ¹³The picked-up of C-pyruvate is to determine the quantitative perfusion in the cardiac muscle.

14. each purposes among the claim 2-4, wherein step b) also comprises the correction of the lactate signal being carried out the amount aspect of bicarbonate, obtains the lactate image through the bicarbonate weighting,

Wherein said correction comprises three operations: i) metabolite and pyruvate image standard are turned to the maximum in each individual images, ii) normalized lactate image be multiply by the pyruvate inverted image, and iii) the intermediate object program that obtains in the aforesaid operations be multiply by initial lactate image

The image of wherein said weighting is applied to above operation i by the metabolite signal that will improve and the metabolite signal combination of reduction together), ii), finish in iii).

15. the purposes of claim 14, described hyperpolarization ¹³The C-pyruvate is as image forming medium, further to estimate cardiac muscular tissue's viability by following steps

(c) minimum by differentiating ¹³C-bicarbonate signal and/or the highest ¹³C-lactate signal, thus in described image, identify risky cardiac muscular tissue.

16. each purposes among the claim 2-4, wherein step b) is necessary.

17. each purposes among the claim 1-4, wherein ¹³The C-pyruvate is ¹³C ₁-pyruvate.

Images